Reference frame encoding method and apparatus, and reference frame decoding method and apparatus

A reference frame decoding method, comprising:

• parsing, by a video decoding device, a bitstream to obtain indication information;
• setting, by the video decoding device, a picture frame on which decoding reconstruction has been performed as the reference frame when the indication information indicates not to construct another reference frame based on the picture frame on which the decoding reconstruction has been performed;
• obtaining, by the video decoding device, a first reference frame when the indication information indicates to construct the other reference frame based on the picture frame on which the decoding reconstruction has been performed, wherein the first reference frame comprising the picture frame on which the decoding reconstruction has been performed or an interpolated picture frame obtained by pixel interpolation on the picture frame;
• parsing, by the video decoding device, the bitstream to obtain mapping parameters;
• determining, by the video decoding device, to-be-determined coefficients of a preset mapping function according to the mapping parameters;
• obtaining, by the video decoding device in the first reference frame according to the preset mapping function whose the to-be-determined coefficients have been determined, a first pixel unit having a mapping relationship with a second pixel unit of a second reference frame;
• and
• assigning, by the video decoding device, a pixel value of the first pixel unit to the second pixel unit to construct the second reference frame.

A reference frame decoding apparatus, comprising:

• a memory storing instructions;
• and
• a processor coupled to the memory, the instructions causing the processor to be configured to:
• obtain a first reference frame comprising a first picture frame on which decoding reconstruction has been performed or a first interpolated picture frame obtained by pixel interpolation on the first picture frame;
• parse a bitstream to obtain mapping parameters;
• determine to-be-determined coefficients of a preset mapping function according to the mapping parameters;
• obtain, in the first reference frame according to the preset mapping function whose the to-be-determined coefficients have been determined, a first pixel unit having a mapping relationship with a second pixel unit of a second reference frame;
• assign a pixel value of the first pixel unit to the second pixel unit to construct the second reference frame;
• obtain a reference frame list comprising a candidate reference frame of the first picture frame on which the decoding reconstruction has been performed;
• obtain regional vertexes of a preset first region in the first picture frame on which the decoding reconstruction has been performed;
• obtain, in the second reference frame according to the preset mapping function, scatters having the mapping relationship with the regional vertexes of the preset first region;
• couple, according to a coupling relationship between the regional vertexes of the preset first region, the scatters in the second reference frame having the mapping relationship with the regional vertexes of the preset first region;
• form a second region using a region encircled by the coupled scatters;
• calculate a ratio of an intersection of areas of the preset first region and the second region to a union of the areas of the preset first region and the second region, wherein the intersection comprises an overlapped location region between the preset first region and the second region, and wherein the union comprises the intersection and a non-overlapped location region between the preset first region and the second region in ranges of the preset first region and the second region;
• add the second reference frame to the reference frame list when the ratio is less than a preset value;
• and
• add the first picture frame on which the decoding reconstruction has been performed to the reference frame list when the ratio is greater than or equal to the preset value.